What’s the Winemaker’s Think Tank?

Every Thursday we will post about a few frequently asked questions that our winemaker has answered. If you have a winemaking question you would like to have answered, please email us at support@juicegrape.com and we will try to get into next week’s post. Cheers! 🙂

How do I bring down my Brix?

                  Sometimes the beautiful California weather can ripen our wine grapes a little too much, sending sugar levels very high. Any grapes with an initial Brix reading over 28 degrees, should be considered high and a winemaker must use caution when fermenting them. The sugars are fermented into alcohol, so many home winemakers think “I will just have a nice strong wine”. While this is correct, the high alcohol levels can lead to a stuck fermentation as the accumulating alcohol levels will begin to kill the yeast. It is very important when selecting your yeast strain, to make sure that is has an alcohol tolerance high enough to handle the sugar in the grapes. You can figure out the end alcohol by volume by multiplying the initial Brix level by .55. Make sure the yeast can handle this end ABV. Another factor to consider is the balance of the wine. Having a very high alcohol content (>14%) can lead to a burning sensation upon ingestion and some off flavors in the wine.

                  Now that we have covered why you may want to bring down your Brix levels, now how does one go about it? You can add water, but because water has a neutral pH, you must add acidulated water as to not bring down the pH of the juice. If your grape must has a pH of 3.6, you must add 3.4g/L of tartaric acid to the water to lower its pH to make it the same strength as the wine must. Then how much water to add? Use the Pearson’s Square formula of the desired amount being equal to the volume of juice in liters multiplied by the desired brix minus the actual brix then divided by the brix of water (zero) minus the desired Brix.

                  In example, if you have a 5 gallon batch of juice at 28 degrees Brix and would like to add water to bring it to 24 degrees Brix, first convert the gallons to liters by multiplying by 3.78 L/gal. This gives you 18.9 liters. Minus the desired Brix of 24 from the actual Brix of 28, to give -4. Multiply the volume by the -4 to give -75.6. Then take the Brix of the additive (water which is zero) and subtract from that the desired Brix of 24. This will give you -24. Then the volume needed is simply -75.6/-24, which gives you 3.15. You would need to add 3.15 liters of water to reduce your Brix from 28 to 24.

We hope this information helps with your winemaking. If you have any follow up questions or winemaking questions in general, please email us at support@juicegrape.com.